Vibratory finishing machine with reversible eccentric drive

ABSTRACT

A vibratory finishing machine including a tub resiliently mounted on a supporting structure and provided with a reversible eccentric vibratory drive system. When the drive system is rotated in one drive direction, eccentric weights align to vibrate the tub at a forceful amplitude. When the drive system is rotated in the opposite drive direction, selected ones of the eccentric weights move to positions out of alignment with the other weights to vibrate the tub at a less forceful amplitude.

Unite States atet [191 Rampe 1 Jan. 14, 1975 [54] VIBRATORY FINISHINGMACHINE WITH 3,608,388 9/1971 Hubner 51/163 X REVERSIBLE ECCENTRIC DRIVE3,618,267 11/1971 Hubner et a1 51/163 [75] Inventor: John F. Rampe,Mayfield Heights,

Ohio

[73] Assignee: Rampe Research, Cleveland, Ohio [22] Filed: Sept. 27,1972 [21] Appl. No.: 292,657

[52] U.S. Cl. 51/163 [51] Int. Cl B241) 31/06 [58] Field of Search51/163 [56] References Cited UNITED STATES PATENTS 3,197,922 8/1965Smith 51/163 3,435,564 4/1969 Balz 51/163 3,449,869 6/1969 Rampe 51/163Primary Examiner-Harold D. Whitehead Attorney, Agent, or FirmWatts,Hoffmann, Fisher & Heinke [57] ABSTRACT A vibratory finishing machineincluding a tub resiliently mounted on a supporting structure andprovided with a reversible eccentric vibratory drive system. When thedrive system is rotated in one drive direction, eccentric weights alignto vibrate the tub at a forceful amplitude. When the drive system isrotated in the opposite drive direction, selected ones of the eccentricweights move to positions out of alignment with the other weights tovibrate the tub at a less forceful amplitude.

11 Claims, 7 Drawing Figures VIBRATORY FINISHING MACHINE WITH REVERSIBLEECCENTRIC DRIVE CROSS REFERENCE TO RELATED PATENTS VIBRATORY FINISHINGMACHINE, U.S. Pat. No. 3,449,869 issued June 17, 1969 to John F. Rampe.

BACKGROUND OF THE INVENTION 1. Field of the Invention The presentinvention relates generally to vibratory finishing machines and moreparticularly to a reversible drive system for vibrating the tub ofafinishing machine at forceful and less forceful amplitudes dependingupon the direction of rotation of the drive system.

2. Prior Art Vibratory finishing machines of the type including a tubresiliently mounted by a supporting structure and provided with aneccentric weight drive system for vibrating the tub are well known. Thereference patent describes one such finishing machine.

It is frequently desirable to adjust the amplitude of vibration of thetub in accordance with the finishing operation to be performed. A moreforceful vibratory finishing action is desirable where large burrs arebeing removed from relatively hard workpiece materials. A less forcefulfinishing action is desirable where a simple polishing action is beingperformed especially on soft workpiece materials.

Two approaches have been used in conjunction with prior art finishingmachines to vary the amplitude of vibration of the tub. One approach isto shut down the machine, remove the guards surrounding eccentricweights of the drive system, and add or subtract weights to provide thedesired tub vibration amplitude. Such an approach is costly both fromthe viewpoint of the amount of down time required for the machine andthe amount of labor time involved in changing the weights.

Another approach is to provide the machine with a variable speed drivesystem whereby the speed of rotation of the eccentrics can be adjusted.This approach has a number of drawbacks since the type of finishingaction carried on in the tub of the machine changes in character inaccordance with the rate of tub vibration. Accordingly, when the speedof rotation of the eccentrics has been adjusted as required to providethe necessary tub vibration amplitude, the character of the finishingaction which results in the tub may be undesirable.

SUMMARY OF THE INVENTION The present invention overcomes the foregoingdrawbacks of the prior art and provides a vibratory finishing machinewith a novel and improved eccentric drive system for vibrating the tubat a selected one of a plurality of amplitudes.

A plurality of eccentric weights are provided. These weights aresupported for selective relative positioning to provide a selectedresultant amplitude of vibratory forces. When the weights are aligned amaximum amplitude is achieved. When the weights are adjusted relatively,the eccentric forces oppose one another to a selected degree to producea resultant force amplitude less than the maximum. In the preferredarrangement the selective positioning of the weights is achieved byreversing the direction of rotation of the drive system.

In accordance with one feature of the present invention a vibratoryfinishing machine of the type including a resiliently supportedfinishing tub is provided with a plurality of rotatably mountedeccentric weights to vibrate the tub. The eccentric weights areselectively interconnected by one or more lost motion connections. Whenthe eccentric weights are rotated in one drive direction they align toimpart a vibratory action to the tub of forceful amplitude. When. theweights are rotated in the opposite drive direction, the lost motionconnections cause one or more of the weights to move out of alignmentwith the remaining weights thereby reducing the effective vibrationproducing weight and accordingly vibrating the tub at a less forcefulamplitude.

In the preferred embodiment, the eccentric drive system includes a driveshaft, a relatively large eccentric weight rigidly mounted along acentral region of the drive shaft, and a pair of smaller weightsdisposed at opposite ends of the central weight and rotatably mounted onthe drive shaft. A notch is formed in each of the smaller weights. Eachnotch receives a drive pin extending radially outwardly from the driveshaft. When the drive shaft is rotated in one drive direction, the drivepins are brought into engagement with one notch surface. When the driveshaft is rotated in the opposite drive direction, the drive pins arebrought into engagement with another notch surface.

In the preferred embodiment, the notch surfaces comprise opposite endsof the notches. When each pin is in engagement with one end of itsrespective notch, the smaller and larger eccentric weights are inalignment and the effective driving weight is the sum of all threeweights. When the drive pins are in engagement with the opposite ends ofthe notches, the smaller weights are disposed on the opposite side ofthe drive shaft from the larger eccentric weight and the effectivedriving weight is the difference of the larger and smaller weights.

As will be apparent, such an arrangement, when driven by a reversiblemotor, provides a drive system capable of vibrating the tub of thefinishing machine selectively at forceful and less forceful amplitudessimply by reversing the direction of rotation of the drive motor. Thereis no need to vary the speed of rotation of the drive motor nor todisassemble the machine to add or subtract weights in order to adjustthe tub vibration amplitude.

Accordingly, it is a general object of the present invention to providea vibratory finishing machine with a novel and improved drive system forselectively varying the amplitude of tub vibration.

Other objects and features will become apparent and a betterunderstanding of the invention will be obtained from the followingdescription and claims when considered in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of avibratory finishing machine incorporating the reversible drive system ofthe present invention;

FIG. 2 is an end elevational view of the machine of FIG. 1;

FIG. 3 is an enlarged exploded perspective view of a portion of thereversible drive system;

FIG. 4 is a foreshortened top plan view on an enlarged scale of aportion of the reversible drive system;

FIG. 5 is an elevational view of a portion of the drive system as seenfrom the plane indicated by line 55 in FIG. 4;

FIG. 6 is a cross-sectional view as seen from the plane indicated by theline 6-6 in FIG. 4; and,

FIG. 7 is a cross-sectional view similar to FIG. 6 but showing thearrangement of eccentric weights which results when the drive system isreversed DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. Iand 2, a vibratory finishing machine constructed in accordance with thepresent invention is shown generally at 10. The machine 10 includes asupporting structure 11 and a tub 12 resiliently carried by thesupporting structure 11.

A pair of vibratory drive systems 13, 14 are disposed along oppositesides of the tub 12. Each of the drive systems 13, 14 includes aplurality of eccentric weights. A pair of reversible synchronous motorsl5, 16 are provided to power the drive systems 13, 14. Electricalconductors l7, 18 extend from a control panel 19 to the motors 15, 16 toenergize the motors 15, 16 in synchronous operation and to control theirdirection of rotation.

The supporting structure 11 includes four uprights interconnected atfloor level by horizontally extending cross members 21. Bolts 22 securethe cross members 21 to a supporting floor surface 23. Four pairs ofelastomeric spacers 25 are interposed between the uprights and the tubstructure 12. The tub structure 12 includes two pairs of horizontallyextending channelshaped cross members 26. The elastomeric spacers extendinto engagement with the cross members 26 and resiliently mount the tubstructure 12.

The tub structure 12 additionally includes an open top receptacle 30adapted to receive finishing media and workpieces to be finished. A door31 is provided at one end of the tub 12 for discharging workpieces andfinishing media onto a chute 32. A pair of relatively heavy structuralchannels 34, 35 extend horizontally along the receptable 30 and arewelded to the receptacle 30. The drive systems 13, 14 are rigidlymounted on the channels 34, 35 such that the vibratory drive motionsgenerated within the drive systems 13, 14 are imparted directly to thetub structure 12.

A motor mounting structure includes a pair of brackets 41, 42 underlyingthe motors 15, 16. The brackets support the motors 15, 16. As isexplained in the referenced patent, the motor mounting platform 40 ispreferably provided with a means of vertical alignment, not shown, formaintaining the alignment of the motors 15, 16 with the drive system 13,14 regardless of the loading of the tub structure 12. Flexible couplings43, 44 connect the motors 15, 16 to the drive mechanism 13, 14 and serveto accommodate the relative motion which takes place between the tubmounted drive mechanisms 13, 14 and the motors 15, 16.

The drive systems l3, 14 are identical in construction and accordinglyonly the drive system 14 will be described in detail. Referring to FIG.1, the drive system 14 includes a pair of bearing blocks 50, 51 whichare rigidly secured to the channel member 35. A drive shaft 52 isjournaled for rotation in the bearing blocks 50, 51. A protective shield53 extends between the bearing blocks 50, 51 and houses three eccentricweights 54, 55, 56.

Referring to FIGS. 3 and 4, the drive shaft 52 has an enlarged centralregion 63. A pair of flat surfaces 64, 65 are provided on oposite sidesof the central region 63.

The eccentric weight 54 comprises a steel plate 60. Fasteners 61 extendthrough apertures formed in the plate 54 and into threaded apertures inthe enlarged central region 63 to clamp the plate 60 rigidly against theflat surface 65.

The eccentric weights 55, 56 include a pair of steel plates 70, 71secured by fasteners 72, 73 to U-shaped mounting structure 74, 75.Apertures 76, 77 are formed through the mounting structures 74, toreceive the shaft 52 and rotatably mount the structures 74, 75 on theshaft 52.

Notches 78, 79 are formed in the mounting structures 74, 75. Theknotches 78, 79 are of U-shaped cross-section and include side surfaces78a, 78b, 79a, 79a and bottom surfaces 80, 81. The notches 78, 79intersect the apertures 76, 77 at right angles thereto in such fashionas divides the bottom surfaces 80, 81 into separate notch surfaces 80a,80b, 81a, 81b.

Driving connections are provided between the weights 55, 56 and theshaft 52 by shaft projections which project radially outwardly from theshaft 52 and into the notches 78, 79. In the preferred embodiment, theshaft projections take the form of drive pins 82, 83. Apertures 84,formed through the shaft 52 receive end regions of the pins 82,83.During assembly the pins 82, 83 are driven securely into the apertures84, 85 to effect a rigid connection between the pins 82, 83 and theshaft 52.

The pins 82, 83 extend radially outwardly from only one end of theapertures 84, 85 and into the notches 78, 79. When the drive shaft 52 isrotated clockwise as viewed in FIG. 6 and as indicated by the arrow 90,the pins 82, 83 are brought into driving engagement with the notchsurfaces 80a, 810. When the drive shaft 52 is rotated counterclockwiseas viewed in FIGS. 6 and 7 and as indicated by the arrow 91, the pins82, 83 are rotated into driving engagement with the notch surfaces 80b,81b. 7

A will be apparent from the foregoing description, rotation of the driveshaft 52 in a clockwise direction as viewed in FIGS. 6 and 7 brings allthree of the eccentric weights 54, 55, 56 into alignment duringrotation. Rotation of the drive shaft 52 in a counterclockwise directionas viewed in FIGS. 6 and 7 cause the weights 55, 56 to assume positionson the opposite sides of the shaft 52 from the weight 54. Accordingly,rotation in one driving direction will vibrate the tub 12 with aneccentric having an effective weight that is the sum of the weights 54,55, 56, while rotation in the opposite driving direction will vibratethe tub with an eccentric having an effective weight that is thedifference of the weights 54 and 55, 56.

Although the invention has been described in its preferred form with acertain degree of particularity, it is understood that the presentdisclosure of the preferred from has been made only by way of exampleand numerous changes in the details of construction and the combinationand arrangement of parts may be resorted to without departing from thespirit and the scope of the invention as hereinafter claimed.

What is claimed is:

l. A finishing machine comprising:

a. a tub structure;

b. structure supporting said tub structure;

c. a reversible rotary vibratory drive interposed between saidstructures for vibrating said tub structure relative to said supportingstructure;

d. means to reverse the rotation of said vibratory drive;

e. said vibratory drive including means to vibrate said tub structure ina first mode at a first amplitude; and

f. said vibratory drive also including means responsive to the directionof rotation of said drive to vibrate said tub structure in a second modeat a second amplitude larger than the first.

2. The finishing machine of claim 1 wherein said vibrating driveincludes:

a. a plurality of rotatably mounted eccentrics; and,

b. positioning means interconnecting said eccentrics and responsive tothe direction of rotation of said drive to reposition selected ones ofsaid eccentrics relative to the other eccentrics to selectively vary theeffective eccentric weight operable to vibrate the tub structure.

3. The finishing machine of claim 2 wherein said positioning meansincludes connection means coupling said selected eccentrics to saidother eccentrics such that rotation of said eccentrics in one drivedirection will bring said selected eccentrics substantially intoalignment with said other eccentrics for vibrating said tub structure atone amplitude, while rotation of said eccentrics in the opposite drivedirection will move said selected eccentrics out of alignment with saidother eccentrics for vibrating said tub structure at a lesser amplitude.

4. A finishing maching comprising:

a. a supporting frame;

b. a tub supported on said frame;

c. vibratory drive means for vibrating said tub rela tive to said frame;

d. said vibratory drive means including a plurality of eccentric weightsand power drive means to rotate said eccentric weights selectively in afirst coordinated mode such that said weights vibrate the tub at a firstamplitude, and in at least one other coordinated mode wherein theweights, when rotated at substantially the same speed as in said firstmode but in the opposite direction, vibrate the tub at a lesseramplitude than the first, and

e. means to reverse the direction the power drive means rotates theshaft.

5. The finishing machine of claim 4 wherein said vibratory drive meansincludes positioning means for selectively positioning selected ones ofsaid weights in a substantially aligned position in order that saidselected weights will have an additive drive effect, and for positioningat least one of said selected weights in a position unaligned with atleast one other of said selected weights in order that said weights willhave a lesser additive drive effect.

6. The finishing machine of claim 5 wherein said positioning meansincludes connection means interposed between said one and said otherweights for positioning said one and said other weights in saidsubstantially aligned position during rotation in one drive direction,and for positioning said one and said other weights in said unalignedpositionn during rotation in the opposite drive direction.

7. In a vibratory finishing machine of the type includ ing a receptacleadapted to receive finishing media and workpieces to be finished, theimprovement of a reversible rotary drive with means connected to thereceptable for vibrating the receptacle in :a first mode at a firstamplitude and with means responsive to the direction of rotation of saiddrive to vibrate the receptacle in a second mode at a second amplitudesmaller than the first, said improvement further including:

a. first and second rotatable eccentric weights;

b. connection means interconnecting said weights and permitting relativemovement of said weights between first and second positions;

c. said connection means being arranged such that rotation of saidweights in one drive direction will effect relative movement of saidweights to said first position while rotation of said weights in theopposite drive direction will effect relative movement of said weightsto said second position;

(1. said weights when in said one first position being substantiallyaligned to vibrate the receptacle at said first amplitude;

e. said weights when in said second position being substantiallyunaligned to vibrate receptacle at said second amplitude less than saidfirst amplitude; and,

. reversible drive means for reversing thedirection of rotation of saiddrive to rotate said weights selectively in said one and said oppositedrive directions.

8. The finishing machine of claim 7 wherein one of said weights issecured to a drive shaft for rotation and the other of said weights isrotatable about the axis of rotation of said shaft between said firstand second relative positions as defined by said connection means.

9. The finishing machine of claim 8 wherein said connection meanscomprises:

a. radially extending projection means carried by said shaft;

b. a pair of spaced surfaces formed on each of said other weights, saidspaced surfaces being engageable one at a time with said projectionmeans to define said first and second positions;

c. said projection means and said spaced surfaces being arranged suchthat when said drive shaft is rotated in one driving direction, one ofsaid spaced surfaces is brought into driving engagement with saidprojection means, and when said drive shaft is rotated in the oppositedriving direction, the other of said spaced surfaces is brought intodriving engagement with said projection means.

10. The finishing machine of claim 9 wherein;

a. said other weight is provided with a notch;

b. said spaced surfaces comprise a pair notch surfaces defining portionsof said notch;

c. said projection means comprises a radially extending shaft carriedprojection which extends into said notch; and

(1. said other weight is movable relative to said shaft betweenpositions where said projection selectively engages one and the other ofsaid notch surfaces.

11. A finishing machine comprising:

a. a supporting frame;

b. a tub supported on said frame for vibration about a generallyhorizontal axis;

c. vibratory drive means on each side of said tub for vibrating said tubrelative to said frame;

(1. said vibratory drive means on each side including means to vibratesaid tube in a first mode at a first amplitude and means responsive tothe direction of rotation of said drive to vibrate said tub in a secondmode at a second amplitude smaller than the first;

e. said means to vibrate the tub in said first and second modes on eachside of the tub including a rotatable shaft parallel to the axis ofvibration of the tub and carrying a plurality of eccentric weights, andpower drive means for said shaft to rotate the shaft and eccentricweights selectively in one of

1. A finishing machine comprising: a. a tub structure; b. structuresupporting said tub structure; c. a reversible rotary vibratory driveinterposed between said structures for vibrating said tub structurerelative to said supporting structure; d. means to reverse the rotationof said vibratory drive; e. said vibratory drive including means tovibrate said tub structure in a first mode at a first amplitude; and f.said vibratory drive also including means responsive to the direction ofrotation of said drive to vibrate said tub structure in a second mode ata second amplitude larger than the first.
 2. The finishing machine ofclaim 1 wherein said vibrating drive includes: a. a plurality ofrotatably mounted eccentrics; and, b. positioning means interconnectingsaid eccentrics and responsive to the direction of rotation of saiddrive to reposition selected ones of said eccentrics relative to theother eccentrics to selectively vary the effective eccentric weightoperable to vibrate the tub structure.
 3. The finishing machine of claim2 wherein said positioning means includes connection means coupling saidselected eccentrics to said other eccentrics such that rotation of saideccentrics in one drive direction will bring said selected eccentricssubstantially into alignment with said other eccentrics for vibratingsaid tub structure at one amplitude, while rotation of said eccentricsin the opposite drive direction will move said selected eccentrics outof alignment with said other eccentrics for vibrating said tub structureat a lesser amplitude.
 4. A finishing maching comprising: a. asupporting frame; b. a tub supported on said frame; c. vibratory drivemeans for vibrating said tub relative to said frame; d. said vibratorydrive means including a plurality of eccentric weights and power drivemeans to rotate said eccentric weights selectively in a firstcoordinated Mode such that said weights vibrate the tub at a firstamplitude, and in at least one other coordinated mode wherein theweights, when rotated at substantially the same speed as in said firstmode but in the opposite direction, vibrate the tub at a lesseramplitude than the first, and e. means to reverse the direction thepower drive means rotates the shaft.
 5. The finishing machine of claim 4wherein said vibratory drive means includes positioning means forselectively positioning selected ones of said weights in a substantiallyaligned position in order that said selected weights will have anadditive drive effect, and for positioning at least one of said selectedweights in a position unaligned with at least one other of said selectedweights in order that said weights will have a lesser additive driveeffect.
 6. The finishing machine of claim 5 wherein said positioningmeans includes connection means interposed between said one and saidother weights for positioning said one and said other weights in saidsubstantially aligned position during rotation in one drive direction,and for positioning said one and said other weights in said unalignedpositionn during rotation in the opposite drive direction.
 7. In avibratory finishing machine of the type including a receptacle adaptedto receive finishing media and workpieces to be finished, theimprovement of a reversible rotary drive with means connected to thereceptable for vibrating the receptacle in a first mode at a firstamplitude and with means responsive to the direction of rotation of saiddrive to vibrate the receptacle in a second mode at a second amplitudesmaller than the first, said improvement further including: a. first andsecond rotatable eccentric weights; b. connection means interconnectingsaid weights and permitting relative movement of said weights betweenfirst and second positions; c. said connection means being arranged suchthat rotation of said weights in one drive direction will effectrelative movement of said weights to said first position while rotationof said weights in the opposite drive direction will effect relativemovement of said weights to said second position; d. said weights whenin said one first position being substantially aligned to vibrate thereceptacle at said first amplitude; e. said weights when in said secondposition being substantially unaligned to vibrate receptacle at saidsecond amplitude less than said first amplitude; and, f. reversibledrive means for reversing the direction of rotation of said drive torotate said weights selectively in said one and said opposite drivedirections.
 8. The finishing machine of claim 7 wherein one of saidweights is secured to a drive shaft for rotation and the other of saidweights is rotatable about the axis of rotation of said shaft betweensaid first and second relative positions as defined by said connectionmeans.
 9. The finishing machine of claim 8 wherein said connection meanscomprises: a. radially extending projection means carried by said shaft;b. a pair of spaced surfaces formed on each of said other weights, saidspaced surfaces being engageable one at a time with said projectionmeans to define said first and second positions; c. said projectionmeans and said spaced surfaces being arranged such that when said driveshaft is rotated in one driving direction, one of said spaced surfacesis brought into driving engagement with said projection means, and whensaid drive shaft is rotated in the opposite driving direction, the otherof said spaced surfaces is brought into driving engagement with saidprojection means.
 10. The finishing machine of claim 9 wherein; a. saidother weight is provided with a notch; b. said spaced surfaces comprisea pair notch surfaces defining portions of said notch; c. saidprojection means comprises a radially extending shaft carried projectionwhich extends into said notch; and d. said other weight Is movablerelative to said shaft between positions where said projectionselectively engages one and the other of said notch surfaces.
 11. Afinishing machine comprising: a. a supporting frame; b. a tub supportedon said frame for vibration about a generally horizontal axis; c.vibratory drive means on each side of said tub for vibrating said tubrelative to said frame; d. said vibratory drive means on each sideincluding means to vibrate said tube in a first mode at a firstamplitude and means responsive to the direction of rotation of saiddrive to vibrate said tub in a second mode at a second amplitude smallerthan the first; e. said means to vibrate the tub in said first andsecond modes on each side of the tub including a rotatable shaftparallel to the axis of vibration of the tub and carrying a plurality ofeccentric weights, and power drive means for said shaft to rotate theshaft and eccentric weights selectively in one of two drive directions,and means coupling at least some of said eccentric weights to the shaftso that rotation of the shaft and eccentrics in one direction will bringthe eccentrics substantially into alignment with one another and vibratethe tub at one amplitude, while rotation of the drive shaft andeccentrics in the opposite direction will move some of said eccentricsout of alignment with others for vibrating the tub at a lesseramplitude, and f. means to reverse the rotation of said vibratory drivemeans.